How do I enable my second Radeon HD6950? I am running DiabloMiner fine with Cayman (#1) running at 312 MHash, but I can clearly tell the second card is not running at all as it is cold.

Linux x64.

Thats not strictly a DiabloMiner question. To mine with multiple cards under any miner under Linux, you must turn off Crossfire. Merely unplugging the bridge does not disable it, you must, as root, run aticonfig --initial -f --adapter=all and then restart X.This will disable Crossfire and make every card individually addressable by all applications.

How do I enable my second Radeon HD6950? I am running DiabloMiner fine with Cayman (#1) running at 312 MHash, but I can clearly tell the second card is not running at all as it is cold.

Linux x64.

Thats not strictly a DiabloMiner question. To mine with multiple cards under any miner under Linux, you must turn off Crossfire. Merely unplugging the bridge does not disable it, you must, as root, run aticonfig --initial -f --adapter=all and then restart X.This will disable Crossfire and make every card individually addressable by all applications.

Thanks, fixed it... was a capturing software I installed that conflicted with the miner. What are the best settings for an HD7970 right now?

-v 1 is what I am using witht he rest stock parameters. You should get ~550mh/s at stock speeds, ~650mh/s overclocked to 1125. You can undervolt these cards quite a bit if you are looking to draw less power. I have mine set to 899mV @ 925/500. I think I can shave off another 10-20mV with further testing. @1125mhz you can go down to around 1050mV.

-v 1 is what I am using witht he rest stock parameters. You should get ~550mh/s at stock speeds, ~650mh/s overclocked to 1125. You can undervolt these cards quite a bit if you are looking to draw less power. I have mine set to 899mV @ 925/500. I think I can shave off another 10-20mV with further testing. @1125mhz you can go down to around 1050mV.

Thanks, will try that... btw, I have been running the miner at 1125MHz clocks and so far, I've gotten 1 "hw error" over the course of a couple hours. Not too sure how concerned I should be about this, would it mean my overclock is possibly unstable?

EDIT: seems it is due to the OC, had to back down to 1060 MHz to get fully stable at stock clocks.

-v 1 is what I am using witht he rest stock parameters. You should get ~550mh/s at stock speeds, ~650mh/s overclocked to 1125. You can undervolt these cards quite a bit if you are looking to draw less power. I have mine set to 899mV @ 925/500. I think I can shave off another 10-20mV with further testing. @1125mhz you can go down to around 1050mV.

Thanks, will try that... btw, I have been running the miner at 1125MHz clocks and so far, I've gotten 1 "hw error" over the course of a couple hours. Not too sure how concerned I should be about this, would it mean my overclock is possibly unstable?

EDIT: seems it is due to the OC, had to back down to 1060 MHz to get fully stable at stock clocks.

1 hw error is basically meaningless. All cards, even at stock clocks, will generate them now and then.